I'm in the same boat you are, just bought one early this week. They seem to be enjoying it and I'm relieved that they didn't just scarf it. I only have 8 birds on it so it looks like it will last for a little while.
I've been useing the flock block for awhile. I thought they would just hang arond the block and eat just that. Not so! They peck at it on and off all day. I think I will be great on those cold/rainy/snowy days in the winter! I highly recommend the flock block!
I'm going to but I'll wait until it's a bit colder. We have a heated dog water bowl that quit working and it's square shaped. I'm hoping it's big enough for a flock block so I can get some more use from it as a flock block holder.
I keep two in my run, one at either end. I find that when it rains or gets wet they distinegrate - they last much longer in dry weather. Every few days I roll the block over - silly chickens think it is brand new all over again and have a ball.